Post on 13-May-2023
INVENTORY ON THE SEAGRASS VEGETATION, ASSOCIATED FAUNA AND FLORAOFSITIO CABU, TAMBLER, GENERAL SANTOS CITY
BY:
BAYBAYON, JOHMAR M.
MAMBALING, DAHLIA F.
OMBANA, MARY GRACE E.
PACOMO, ABEL L.
MARCH, 2014
1. INTRODUCTION
1.1 Rationale
Philippine archipelago has been designated as one of the World’s top 19
biodiversity hotspots, and in fact is in the top five in this elite
group (Philippines’ Biodiversity: A Conservation Imperative, 1992).
Unfortunately, the Philippines is also the world leader in degree of
endangerment, with only 6-8% of natural vegetation remaining and for
less than that in primary condition—leading to the dubious distinction
of generally being considered the hottest of the hotspots and the most
severely endangered of the Mega diversity countries.
Sea grass meadows provide ecosystem services that rank among the
highest of all ecosystems on earth. Sea grass beds have long been
identified as an important habitat for fishes and invertebrates (Orth et
al., 1984). Experimental studies investigating some of the mechanisms
thought to make sea grass a preferred habitat found that food
availability, refuge from predation, increased living space, and habitat
richness were important (Jordan et al., 1996). There are only about 50
species of sea grass in the world and the Philippines has 16 taxa
recorded where Fortes added three new taxa to the list holding a record
of second to Australia which has 17.Sea grasses provide protective
shelter for many animals, including fish, and can also be a direct food
source for manatees and dugongs, turtles, some herbivorous fish and sea
urchins. The roots and rhizomes of sea grasses also stabilize sediments
and prevent erosion while the leaves filter suspended sediments and
nutrients from the water column (Costanza, 1997).
Macro algae play important roles in the ecology of coral reefs.
They are the major food source for a wide variety of herbivores and are
the basis of the reef food-web, they are major reef formers, and they
create habitat for invertebrates and vertebrates of ecological and
economic importance (Costanza, 1997). They also play critical roles in
reef degradation, when abundant corals are often replaced by abundant
macro algae. This may result from over-fishing of herbivorous fish or
from pollution by excess nutrients and sediments. Increased macro algae
on a coral reef are often undesirable, indicating reef degradation,
although this depends on the type of algae (Duarte, 1999).
There is a degrading seagrass and seaweed beds due to human
interventions and their importance to ecosystem is still of issue mainly
due to lack of information. This assessment is done to identify the
species of seagrasses and seaweeds that can be found in the area. Data
in this assessment and inventory is a significant contribution for the
conservation of remaining vegetation.
1.2. Objectives of the study
1.2.1 General Objective
The study aims to assess the species diversity of sea grasses as well as
those associated seaweeds. Also, todetermine its frequency, relative
frequency, density, relative density, dominance and percent cover of sea
grasses beds.
1.2.2 Specific Objective
The study aims to identify and determine the species composition of sea
grasses and its associated fauna and flora. In addition, it also aims to
determine the specific substrates where a specific species thrives as a
result of a zonational pattern.
1.3. Significance of the Study
This assessment is a significant tool for evaluating the ecological
indices of the sea grass vegetation in Sitio Cabu, Barangay Tambler,
Santos City. In addition, it is also significant in determination
of different plants and marine invertebrates that thrive in sea
grasses. This would also serve as a baseline data for future study in
the area. Furthermore, the results can be used as a reference for future
related researches and studies. It could also be used as a tool for a
large scale coastal management.
1.4 Scope and limitation
The assessment would only in the Stio Cabu, Tambler, General Santos
City. It is limited only in assessment of seagrass and the
identification of associated fauna and flora. Furthermore, the
identification of sea grass and seaweeds are up to species level. In
addition, the substrates where the floras are found are recorded in the
slate board.
2. REVIEW OF RELATED LITERATURE
2.1 Seagrass
Seagrasses are not grasses at all. They are flowering plants but they
are not closely related. Close family of seagrass are the lilies. Most
of the species are found in tropical waters. Meadows are especially well
developed in Caribbean coral reefs, where they play an important role in
the stabilization of sediments on less exposed side of the reef.
Seagrass are important, but their role has often been overlooked due
largely to their submerged state. Thayer, Wolfe, and Williams (1975)
state that sea grass bed is more productive than of the cultivated corn.
It also supports a large number of epiphytic organisms, with a total
biomass perhaps approaching that of the sea grass itself. It helps in
active sulfur cycle and initiates sulfate reduction. It also serves as
defense in erosion, thereby preserving the microbial flora of the
sediment and the sediment- water interface. Its leaves the current that
give nutrients within its area. According to den Hartog (1984) sea
grasses are marine angiosperms with a worldwide distribution.
Taxonomically it is quite a small group with only a total of around 60
species. However, their ecological importance is undisputed.
Seagrass ecosystems are one of the main components within the
tropical seascape (Moberg and Rönnbäck 2003) and their presence causes a
dramatic increase in biodiversity of both plants and animals as they act
both as shelter for juvenile animals and as a foraging and nursery area
for many animal species (Larkum et al. 1989, Duarte 2002). Furthermore,
they have a main function as stabilizers of tropical coastal habitats as
they trap nutrients and sediments carried from terrestrial effluents,
protecting coral reefs from turbid waters and beaches from wave erosion.
Sea grass beds also play an important role as indicators of
coastal ecosystem health. Because they are highly sensitive to changes
in environmental, physical, chemical and biological conditions, sea
grass health is used as a sensitive index of the impact of the
activities developed in the area. Short et al. (2007) stated that Sea
grasses represent the dominant component of many shallow marine
habitats. Many sea grass meadows consist only of one sea grass species,
although mixed stands containing up to 14 species may be found in the
tropics, particularly in the Indo-Pacific region which has the highest
sea grass biodiversity on earth. Sea grass meadows are, on an area
basis, very productive ecosystems with an average standing stock sea
grass dry weight of 460 g per m2 and an average growth rate of 5 g dry
weight per m2 per day (Duarte and Chiscano 1999).
2.2 Seaweed
Algae are defined as oxygenic photo synthesizers other than embryophyte
land plants (Cavalier and Smith, 2007). In recent years our knowledge of
these organisms has greatly advanced, thanks to new types of data
(mainly electron microscopy observations and DNA sequence data). Based
on these data, we know now that algae represent an artificial and
unnatural agglomeration of very different organisms, sharing the only
common characteristic of living in aquatic habitats. Algae living in the
sea are typically subdivided in plankton (the complex of microscopic
algae not visible with unaided eye, which live floating in the water)
and benthos (the collectivity of the algae that live attached to the sea
bottom).The seaweeds exhibit an astonishing variety of aesthetic and
diverse life forms throughout the shallow seas of the world. While it is
estimated that there are c. 10,000 species of red, brown and green
seaweed, a great deal more knowledge is needed on how much diversity
exists and where species are distributed. Seaweeds are particularly
useful organisms for studying diversity patterns and planning the
conservation and sustainable use of inshore marine resources, and are
also useful as indicators of climatic change (Van der Strate et al.
2002). They are relatively easy to collect, fixed to the substratum,
often form relatively stable assemblages, and have relatively similar
species numbers in richer temperate and tropical regions. The algae that
form the benthos are plant-like organisms, very diverse and very
different in size, shape and color; they are typically designated with
the term seaweeds. Despite of the undeserved negative connotation
associated with such a name, seaweeds play fundamental role marine
ecosystems, where they have a multitude of beneficial effects. Seaweeds
occur on any shore where a hard bottom or any other types of stable
surfaces are present.
It was reported that seaweeds are an ecologically and economically
important component of marine ecosystems worldwide (Prathep et.al.
2006). They are primary producers and provide shelter, nursery grounds,
and food sources for marine organisms. Around the world they are also
used as foods and fertilizers, as well as for the extraction of valuable
commercial products including cosmetics. Recent research has pointed to
new opportunities, particularly in the field of medicine, associated
with bioactive properties of molecules extracted from seaweeds, using
them as a CO2 sink or even as bio-fuel.
Fig.1. Study area: Sitio Cabu, Tambler, General Santos City
3.1.1. General description
The area has sandy and rubbles substrates with outcropping stones
in the area. The area is composed of different species of sea grasses
including Syringodium isoetifolium, Halophila ovalis, Cymodocea serrulata, Cymodocea
rotundata, Halodule pinifolia. The firstseagrass and seaweed vegetations are
approximately 38 meters away from the shoreline as measured from the
highest tide (flotsam).
3.2. Methods
The transect-quadrat technique method (Saito and Atobe, 1970) was used
in assessing sea grass and seaweed. A transect line of 50-meter
fiberglass tape was used to setacross the seagrasses vegetation
perpendicular to the shore at each designated station. The starting
point is at 06.018680 N and 125.139470 E then it ends at 06. 01825 N and
125.13959 E. A four quadrat measuring 50x50cm (0.25 m2) shall be set
along the transect line in each station at10-meter interval. Surface and
bottom temperatures and salinities were determined on each transect. The
number of shoots of every sea grass species was counted on 5
representative grids on each quadrat established on every station. The
number of grids on which each sea grass species was present was also
counted (English et al., 1994).
3.2.1. Materials
The following are important materials used in the assessment with
their specific functions:
Table 1. List of material and their uses
Materials Uses
Transect line measuring the distanceQuadrat Parameter or area for
counting the shoots of sea grass and seaweeds.
slate board recording of data
snorkel and mask Snorkeling
3.3. Data analysis
After the data was gathered, the following computations are going to be
used in order to correlate the data afterwards (English et al., 1994).
a.) Frequency
Total no. of segments in whichSpecies A occurs
f = ---------------------------------------------x 100Total no. of segments sampled
b.) Relative Frequency (RF)
f value of Species ARf= ----------------------------------x 100Total f value of all sp.
c.) Density (Den)
No. of individuals ofSpecies ADen = ------------------------------------------------x 100
Total no. of individuals for all sp.
d.) Relative Density (RDen)
RDen=Density of species Ax100Total Density of all species
e.) Percent cover
Adapted from Saito and Atobe (1970)
4. RESULTS AND DISCUSSION
The following are the data gathered after the assessment. Different
species of seagrass and associated fauna and flora were observed present
on the area of study.
4.1 Result of the Assessment of Sea grass Species Coverage
Species Family Substrates
Halophilaovalis
(Spoon Seagrass)
Hydrocharitaceae Sandy, rubbles
Halophila minor Hydrocharitacea sandy
Cymodoceaserrulata Hydrocharitaceae coarse sand mixed with coraland shell debris
Halodulepinifolia Potamogetonaceae Sandy near the shoreline
Table 2. Sea grass substrates preference
Syringodiumisoetifolium Potamogetonaceae Sandy,muddy,rubbles
Figure 2. Percent Cover of the Sea grass Species of Sitio Cabu, Tambler,General Santos City
Figure 3. Frequency of the Seagrass Species of Sitio Cabu, Tambler,General Santos City
Figure 4. Relative Frequency of Sea grass Species of Sitio Cabu,Tambler, General Santos City
Figure 5. Density of the Seagrass Species of Sitio Cabu, Tambler,General Santos City
Figure 6. Relative density of the Seagrass Species of Sitio Cabu, Tambler, General Santos City
Figure 7. Dominance indices of the Seagrass Species of Sitio Cabu,Tambler, General Santos City
4.2.2 Sea grass Species Compositions of Sitio Cabu, Tambler, GeneralSantosCity
Fig 8. Halophila ovalis (R. Brown, 1858)
Kingdom: PlantaePhylum: TracheophytaSubphylum: EuphyllophytinaInfraphylum: SpermatophytaeSuperclass: AngiospermaeClass: MonocotsOrder: AlismatalesFamily: HydrocharitaceaeGenus: Halophila
Halophilaovalis is typically found growing from mid-tidal range to
depths down to 12 meters. Its preferred substrate type is sand and mud
bottoms, but spoon grass has been observed in a variety of substrates
ranging from soft mud to coarse coral rubble. Itsleaves are oblong-
elliptic with rounded tips and occur in pairs. The leaf blades measure
approximately 1-4cm long with lengths sometimes reaching up to 7cm and
0.5-2mm wide. The rhizomes are thin, up to 2mm in diameter, with one or
more roots at each node.
Fig.9.Cymodocea serrulata(Asch. & Magnus)
Kingdom: PlantaePhylum: TracheophytaSubphylum: EuphyllophytinaInfraphylum: SpermatophytaeSuperclass : AngiospermaeClass : MonocotsOrder: AlismatalesFamily: HydrocharitaceaeGenus: Cymodocea
It grows on muddy sand, fine sand or sand with coral
rubble substrates in the intertidal zone. It is a mid-
successional species, and can colonize very quickly once
established. This species can quickly recover or return after a
disturbance.Linear strap-like leaves, 5-9mm wideand serrated leaf
tip.
Fig. 10.Halophila minor (den Hartog, 1985)
Kingdom : PlantaePhylum : TracheophytaSubphylum: EuphyllophytinaInfraphylum: SpermatophytaeSuperclass: AngiospermaeClass: MonocotsOrder: AlismatalesFamily : HydrocharitaceaeGenus: Halophila
.This species normally grows on coral sand or muddy sand together
with H. ovalis or with other tropical seagrasses in shallow water. It
also extends into deeper water down to seven m where it forms sparse
patches with other species such as Halodule pinifolia (Kuo et al. 2006).
Fig. 11.Halodulepinifolia (Miki, 1964)Kingdom: PlantaePhylum: TracheophytaSubphylum : EuphyllophytinaInfraphylum: SpermatophytaeSuperclass: AngiospermaeClass : MonocotsOrder: AlismatalesFamily: CymodoceaceaeGenus: Halodule
This species occurs in the sublittoral zone, typically growing on
sandy or muddy bottoms. It has been observed in both high and low energy
environments, but mostly resides in sheltered bays and pools.
Halodulepinifolia is characterized by long, narrow leaf blades measuring 5-
20cm in length and 0.6-1.2mm in width. The leaf tip is widely rounded
and serrated. The leaf sheaths are approximately 1-4cm long.
Halodulepinifolia has a creeping rhizome with 2-3 roots at each node.
Fig.12Syringodiumisoetifolium (Ascherson, 1939)
Kingdom: PlantaePhylum: TracheophytaSubphylum : EuphyllophytinaInfraphylum: SpermatophytaeSuperclass : AngiospermaeClass: MonocotsOrder: AlismatalesFamily: CymodoceaceaeGenus: Syringodium
Noodle sea grass typically occurs on muddy substrates in depths
down to 6 meters, but has been observed on sandy bottoms in depths down
to 15 meters.Syringodiumisoetifolium can form monospecific meadows; however,
it is usually associated with other seagrasses, including
Cymodocearotundata, Cymodoceaserrulata, Haloduleuninervis and Thalassiahemprichii.
This sea grass has a thin rhizome with 1-3 slightly branched or
unbranched roots at each node. A short stem is also present at each node
bearing 2-3 leaves. Leaf blades are cylindrical approximately 7-30cm
long and 1-22mm wide and narrow towards the base. There is a central
vascular bundle within the leaf blade surrounded by a circle of 6-8 air
channels and 7-15 pericentral vascular bundles.
4.2. Associated Flora
Sitio Cabu, Tambler, General Santos City has also a diverse array of
seaweeds associated with the sea grass bed. It has a sandy substrate on
shallow area with some rocky portion and scattered rubbles.
4.2.1 Seaweeds Species Compositions of Stio Cabu, Tambler, general
Santos City
Fig 13.Acanthophora spicifera (Vahl) Børgesen, 1910
Kingdom: PlantaeDivision: RhodophytaClass:
FlorideophyceaeOrder: CeramialesFamily:RhodomelaceaeGenus: Acanthophora
It has a large, irregularly shaped holdfast for attachment to hard
bottoms. From the holdfast, erect fronds begin to branch out. The main
branches have short, determinate branchlets that are irregularly shaped
and spinose. Branchlets are hook-like, brittle and fragment easily under
heavy wave action. Color is highly variable, and can be shades of red,
purple, or brown (Littler and Littler, 1989).
Fig 14.Bornetella oligospora
Kingdom: PlantaePhylum: ChlorophytaClass: DasycladophyceaeOrder: DasycladalesFamily: DasycladaceaeGenus: Bornetella
Thallus bright green, clavate, to 2–4 cm in height, 3–6
mm in diameter. Structure with 24–30 primary laterals per
whorl, each branching into (3–)4(–5) secondary segments that
form a faceted cortex. Each facet with one dichotomously
branched, eventually deciduous, hair.Epilithic in the shallow
subtidal and lower intertidal, often occurring in dense
clusters.
Fig 15. Caulerpasertularioides (J. Agardh,1847)
Kingdom: PlantaePhylum: ChlorophytaClass: UlvophyceaeOrder: BryopsidalesFamily: CaulerpaceaeGenus: Caulerpa
Frond: erect, feather-like, occasionally branched, to 20 cm high,
1-2 cm wide, light green. Branchlets opposite, cylindrical, needle-
shaped, 180-330 µm diam., 3-11 mm long, upcurved or straight; apices
bluntly pointed. Central axes cylindrical, 1.0-1.5 mm diam. Stolons
creeping, extensive, 2.0-2.5 mm diam., to 2 m long, generally shorter;
rhizoids thickly stalked, to 2 mm diam. at stolon, branching to slender
apices.
Fig 16.Halimedaincrassata(J. Ellis, 1816)
Kingdom: PlantaePhylum: ChlorophytaClass: UlvophyceaeOrder: BryopsidalesFamily: HalimedaceaeGenus: Halimeda
The plants are erect and grow to a height of about 20 to 24 cm.
They have a well-developed, thick, heavily calcified stalk above which
the branches are more or less in one plane. The segments are flat and
usually 3-lobed. They are dull green in the upper portions and whitish
near the base. Most commonly found in shallow sandy areas, including
seagrass beds.
Fig 18. Gracilaria cervicornis (Turner, 1852)
Kingdom: PlantaePhylum: Rhodophyta
Subphylum: EurhodophytinaClass: FlorideophyceaeSubclass: RhodymeniophycidaeOrder: GracilarialesFamily: GracilariaceaeGenus: Gracilaria
Plants of the largest species can reach 60 cm in length. Thalli
range from erect to prostrate and from terete to broadly flatten. Some
species form articulated fronds composed of cylindrical or irregularly
shaped units..
Fig 19.Halimedaopuntia (Linnaeus, 1816)
Kingdom: PlantaePhylum: ChlorophytaClass: UlvophyceaeOrder: BryopsidalesFamily: HalimedaceaeGenus: Halimeda
They have hick, profusely branched clumps of rounded three-lobed
or ribbed leaf-like segments, between 10 and 25 cm in height. The
branches are numerous and are in different planes, rather than nearly in
a single plane as some other species are. This alga can cover larger
areas with a dense mat so that individual plants are indistinguishable.
They grow in shallow depressions, cracks and crevices, between hard
corals and other somewhat protected areas of the reef, down to 55 m.
Fig 20. Turbinaria ornata (Turner) J. Agardh
Kingdom: PlantaeDivision: PhaeophytaClass: PhaeophyceaeOrder: FucalesGenus: Turbinaria
Found primarily in tropical marine waters. It generally grows on
rocky substrates. In tropical Turbinaria species that are often
preferentially consumed by herbivorous fishes and echinoids, there is a
relatively low level of phenolics and tannins.
Fig. 21 Gracilariaverrucosa (Hudson, 1950)
Kingdom: PlantaePhylum: RhodophytaSubphylum: EurhodophytinaClass: FlorideophyceaeSubclass: RhodymeniophycidaeOrder: GracilarialesFamily: GracilariaceaeGenus: Gracilaria
Fig.22 Eucheuma cottonii
Kingdom: PlanrtaePhylum: RhodophytaClass: RhodophyceaeOrder: GigartinalesFamily: SolieriaceaeGenus: Eucheuma
This alga grows to two meters long and is green or yellow in
color. Eucheuma are typically found below the low tide mark to
the upper subtidal zone of a reef, growing on sand to rocky
seafloor areas along a coral reef, where water movement is slow
to moderate.Their growth is similar to terrestrial plant species,
where eucheuma have a growing tip, or apical meristem, which is
also capable of dividing to form new growing branches.
Fig 23. Galaxaura oblongata (J.Ellis & Solander) J.V.Lamouroux, 1816
Kingdom: PlantaePhylum: RhodophytaClass: FlorideophyceaeOrder: NemalesFamily: GalaxauraceaeGenus: Galaxaura
Red algae that grows on rocks, coral rubbles. Dredged from
rocky substrata at depths of 13 to 18 meter plus another record
at 37 m depth
Fig 24 Gracilaria canaliculata
Kingdom: Plantae Phylum: Rhodophyta Class: Florideophyceae Order: Gracilariales Family: Gracilariaceae Genus: Gracilaria
Thalli are terete, 5-13 cm in height, attached to the substratum
by a large discoid holdfast and by secondary holdfasts formed on
lower portion of branches. Branches are subdichotomously,
unconstricted with obtuse apices. Fresh plants firm in texture
and are light to bright red in color. Surface of the branches are
usually covered with many translucent white spots throughout.
Hair cell is present, borne in clusters visible as white spots on
the frond surface.
4.3 DISCUSSION
Sitio Cabu, Tambler, General Santos City has a sea grass bed with a
sandy substrate with outcropping stone and rubbles. The area is composed
of different seagrass species that seems to have a zonation pattern .It
is composed of two sea grass families, Potamogetonaceae (2 genera, 2
species) and Hydrocharitaceae (3 genera, 3 species). Evidently, sea
grasses are very susceptible to change in physical and chemical
properties of the ocean and with global warming, which is changing the
temperature of the ocean.
As shown on Figure 2, S. isoetifolium (29.45%) has the most highest
percent cover, followed by Halodule pinifolia (25.83%), Cymodocea serrulata
(24.13%) and Halophila ovalis (18.73%) respectively. On the other hand, H.
minor (14.45%) has the lowest percent cover among all species in the
area.
In terms of frequency, Halophila ovalis is the most frequent species
(54.17%), followed by Halodule pinifolia (50%), Cymodocea serulata (37.5%),
Syringodium isoetifolium (33.3%) mand Halophila minor (20%) has the lowest
frequency (see fig 5). Meanwhile, in relative frequency Halophila ovalis is
the most frequent species (27.77%), followed by Halodule pinifolia (27.7%),
Cymodocea serulata (19.22%), Syringodium isoetifolium (17.1%) and Halophila minor
(10.3%) has the lowest realative frequency (see fig 4).
Furthermore, theS. isoetifolium (36.53%) has the highest density among
all the species, followed by H.pinifolia(27.7%),H. ovalis (19.22%)cymodocea
serrulata (15.8%). On the other hand, Halophila minor (0.8%) has the
lowestdensity (See figure 5).
In terms of dominance, Halophila ovalis (74.09%) got the highest dominance among
all species, followed by Halodule pinifolia (64.49%), Syringodium isoetifolium
(52.34%). Halophila minor (20.8%). While, cymodocea serrulata(5.33%) got the
lowest dominance (see figure 7). The area is dominanted by Halophila
ovalisdue to the strong current that was present in the area.
Most seagrasses are limited in their distribution at the
intertidal to the shallow subtidal zone in the marine environment
although a few may be found high in the supratidal zone (spray zone).
The difference in their distributional patterns is reflective of their
ability to adapt to the ambient ecological condition in their habitat.
The presence of a species in a certain habitat is dependent on their
ability to adapt to the synergistic effects of the different ecological
factors in the environment.
In the study area seagrassess thrive at different substrates. Some could
be seen in outcropped stones and rubbles while moist of the species
could be seen in sandy portion. It was observed that sea grass beds
harbor a wide array of flora and fauna. Plant-animal interaction in the
sea grass beds is one of the major areas of expanding near shore
research that emphasize the importance of seagrass in the structuring of
faunal assemblages in the seagrass communities (Nakaoka, 2005). In some
station, sea cucumber juvenile could be seen sheltered in the leaves of
sea grasses especially on species with wide leaves. Other invertebrates
could also be seen in seagrass beds such as hermit crab, polychaete
worm, crinoids, and brittle star. A variety of seaweeds also thrives
with the sea grasses.
5. SUMMARY AND CONCLUSIONS
This chapter includes the summary of findings, conclusions and
recommendations made by the researcher based on the results of the
study.
5.1 Summary
Sitio Cabu, Tambler, General Santos City has a sea grass bed
with a sandy substrate with outcropping stone and rubbles.There are two
seagrass families, viz. Potamogetonaceae (2 genera, 2 species) and
Hydrocharitaceae (3 genera, 3 species) identified in the study area.
Halophila ovalis yields the greatest frequency (54.17%) and relative
frequency (27.77%) and the most dominant species with (74.09%).
Meanwhile, Syringodium isoetifolim is the densest species in the area with
adensity of 36.53% and relative density 19.04%. On the other hand, it
also has the highest percent cover in the area.
The area is of mostly sandy substrates with rubbles teeming with
algae and other marine invertebrates such as juvenile sea cucumber,
hermit crab, polychaete worm, crinoids, and brittle star.
5.2 Conclusion
Based on the data presented the following conclusions were drawn:
The study area is composed of two sea grass families,
Potamogetonaceae (2 genera, 2 species) and Hydrocharitaceae (3
genera, 3 species).
Halophila ovalis yields the greatest frequency and relative frequency,
relative density and the highest percent cover.
Syringodium isoetifolium has the highest percent cover in the area
making it the densest species.
The associated flora (marine algae) in the area is composed of
eight species (5 Rhodphyta, 2 chlorohyta and 1 Phaeophyta).
Halophila ovalis yields the greatest frequency and relative
frequencyand the most dominant species in the area due to the
physical properties of the study area.
The seagrass vegetation of the area is a mixed bed of seagrasses
and is a home for various marine invertebrates as well as the
juvenile fishes and different species of seaweeds.
Based on the result of this study the researchers recommended as a
force of action to be taken to have atleast an annual or periodic
assessment of the sea grass and its associated flora and fauna Sitio
Cabu, Tambler, General Santos City. It is for the purpose monitoring the
diversity of the marine flora as well as the faunal assemblages that
thrives in the area.
For further studies, the researchers also recommended an in depth
study on how the physical and chemical parameters of the area affects
the diversity of sea grasses and seaweeds as well as their associated
fauna that thrive in the area. In addition, It was also recommended by
the researchers to extend the assessment to the other coastal area of
the General Santos City.
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7. APPENDICES
Transect 1stations
Species present
No. of grids present
No. of shoot per 1x5 grid per quadrat
Associated fauna
Station 1 Syringodium isoetifolium
Q1=23Q2=22Q3=25Q4=25
59, 35, 38, 45, 4532, 36, 37, 35, 3654, 62, 51, 50, 5759, 58, 70, 68, 64
Hermit crabAlgaePolychaete worm Sea cucumber
Halophila ovalis
Q1=23Q2= 23Q3= 24Q4= 24
27, 19, 29. 22, 1619, 12, 21, 22, 2822, 29, 19, 29, 2117, 29, 26, 25, 27
Cymodocea Q1= 17Q2= 20Q3= 23Q4= 23
13, 24, 35, 13, 1718, 14, 14, 9, 1532, 35, 19, 15, 2318, 18, 38, 35, 32
Halodule Q1=1Q2= 2Q3=9Q4=5
277527
Station 2 Syringodium Q1=14Q2=15Q3= 8Q4= 12
14, 17, 2, 13, 2017, 0, 11, 18, 183, 16, 10, 7,24, 5, 6, 13,
crinoidshermit crabbrittle starhydroids galaxauraturbinaria
10 halimedaHalophila Q1= 13
Q2= 16Q3= 13Q4= 19
21, 17, 12, 17, 1527, 47, 36, 16, 4016, 14, 21, 26, 3234, 25 38, 41, 31
Halodule Q1= 17Q2= 6Q3= 7Q4= 6
69, 46, 46, 21, 225, 7, 3, 6, 08, 10, 11, 0,820, 7, 7, 0, 6
Station 3 Halophila Q1= 0Q2= 0Q3= 0Q4= 3
0003
Halodule Q1= 0Q2= 2Q3= 0Q4= 0
0400
Station 4 Halophila ovalis
Q1= 9Q2= 5Q3= 10Q4= 6
5, 0, 6, 3, 04, 1, 1, 0, 00, 0, 9, 4, 20, 0, 0, 5, 3
Halophila minor
Q1= 4Q2= 7Q3= 0Q4= 10
0,2, 2, 6, 66, 2, 0, 2, 000, 0, 0, 5, 5
Station 5 Halodule Q1= 16Q2= 24Q3= 5Q4= 4
5, 4, 10, 4, 65, 5, 6, 7, 71, 1, 1, 1, 10 ,0, 0, 6, 2
Cymodocea serrulata
Q1= 9Q2= 0Q3= 12Q4= 2
3, 3, 2, 3, 400, 2, 2, 6, 60, 0, 0, 2, 0